Horticulture Magazine

Camassia ‘Camas’

Camassia leichtlinii in a cottage garden

Overview

Official Plant NameCamassia
Common Name(s)Camas, Quamash, Wild Hyacinth, Camosh
Plant TypePerennial Bulb
Native AreaWestern North America
Hardiness RatingH4
FoliageDeciduous; Grass-like
FlowersSix-tepalled, star-shaped blossoms
When To SowSeptember, October
Flowering MonthsMay, June
Sunlight

Preferred
Full Sun / Partial Shade

Exposure
Sheltered

Size

Height
0.5 – 1.5M

Spread
0.1 – 0.5M

Bloom Time
May – June

Soil

Preferred
Any

Moisture
Moist but well drained

pH
Any

Six-tepalled, star-like blooms in dense flower-laden racemes on erect stalks in pastel tones and deep shades of purples will adorn your garden if you plant a few Camassias.

This very reliable, virtually no-care perennial bulb plugs that spring-to-summer transition season. It hails from the sunny prairies and moist meadows of the United States where it paints the landscape in big, broad blazes of colour.

Camassia is a long-lived deciduous perennial that has probably flown under the radar of a goodly number of gardeners and anthophiles.

This easy-grow and very well-behaved bulb will keep coming up year after year and naturalise in your garden, but ever so gradually and ‘tactfully.’ You don’t have to worry about Camassia pulling a no-show, and you don’t have to worry about Camassia taking over your garden. 

Camassia, also called Camass Lily, actually originally used to be classified with Lilies in Family Liliaceae. After the usual Botanical shuffles and reshuffles, Camassia’s lot fell with… Asparagus in Family Asparagaceae!

Which is not inapt because Camassia, known as Quamash to Native Americans in the Western States, was a nutritious food for the Nez Perce, Cree, and several other tribes a few centuries ago. The bulbs were also consumed by the Western frontier’s pioneers.

And this factoid brings us to a third name for this plant: in most parts of the United States it still goes by what the pioneers called it: Camas, a corruption (or phonetic simplification) of the Native American name.   

Camassia quamash on a flood plain in Oregon
A Blaze of Camassia quamash in Bloom on a Prairie in Oregon

Camassia includes all of six species and a handful of cultivars.

While the species range quite widely in height, running from only about 30 centimetres all the way to 1.3 metres, all varieties – species and cultivars – have similar foliage which comprises of clumps of narrow linear leaves.

The leaves are either narrow or narrower; from strap-like to grass-like. Camassia leichtlinii and its cultivars’ foliage is of a ‘Nature Fresh’ shade of green; Camassia quamash’s foliage has a bluish tinge.

This bulb starts blooming after Tulips have displayed their charms and shut up shop. Camassias light up gardens and meadows between Flowerdom’s two peak seasons, producing blooms through May, moving into June.

Flowers are five to seven centimetres wide and have narrow ray-like tepals, six in number, in a perfect star shape.

Colours include creamy white, and shades of blue and purple from the palest lilac through to the deepest violet. The bright, sunny yellow stamens make a striking contrast on the flowers that are in brilliant hues of purple and violet.

Camassia flowers’ frothy racemes are borne on stiffly upright stalks, but not so stiff that they cannot sway a little in a fair breeze. As for those racemes and stalks, each one bears about 80 flowers and sometimes more – now isn’t that floriferous?

Like most such upright racemes, the buds open sequentially from bottom to top, thus putting on a continuing show over many days. They will also put on an equally good show inside the house as cut flowers are strong and long-lasting in a vase.

deep purple Great Camas with yellow stamen
Star-Shaped Rich Purple Flowers of Camassia leichtlinii in Full Bloom

Background and Origins

For such an attractive flowering bulb that has impressive ornamental merits, it is surely amusing that historically Camassia’s value lay in being a source of food!

Various Camassia species, in particular Camassia quamash, used to be actively cultivated as a food crop in exclusive plots of land by Native American tribes in the American North-West.

Care and harvesting of Camassia bulbs was the responsibility of the women while the men roasted or baked the bulbs in pits. 

Camassia scilloides or Atlantic Camas is the only one of the six species that is native to Eastern North America. Its bulbs too were an important source of food for the tribes inhabiting those regions.

Camassia quamash and Camassia leichtlinii were first analysed in 1827 and two or three decades later had found their way to gardens in established colonial cities of the East whence specimens were taken to Great Britain in the late 1850s. 

Though not as wide-ranging as it was in the time of Lewis and Clark, Camassia still blooms prolifically in extensive swaths of land in the American West, painting prairie and meadow with blazes of colour as spring transitions into summer.

Camassia bulbs on a wicker background

Common Varieties

C. leichtlinii is probably the most floriferous of the species. It is also one of the tallest considering that spikes top out at 1.3 metres. Its leaves are strap-like and not as narrow as those of the other species. Its flowers are a rich purple. It grows wild from British Columbia down to California. It is the most cultivated among the six species.

C. leichtlinii subsp. suksdorfii Caerulea Group also bears purple flowers but of a pleasant, mid-tone hue. It too can reach about 1.3 metres. This is one of the most widely available and popular varieties.

C. leichtlinii Caerulea Group in strong contrast grows to only about 30 centimetres. Its flowers too are more toned down, being of a pastel lilac-purple colour. Do not confuse this variety with similarly named ones which are taller.

Camassia leichtlinii blossoms
Petite and Purple – Camassia leichtlinii Caerulea Group Beginning to Bloom

C. cusickii is probably the most leafy of the species. It too is one of the tallest as spikes can reach 1.3 metres. The flowers’ tepals are especially narrow, almost wispy. They are of a cool, pastel tone of lilac often shifted to blue. It is a native of Oregon.

C. quamash has the most extensive range; it grows in a large swath of western North America. It reaches a height of not much more than 30 centimetres. Its foliage is comparatively limp. The flowers are a saturated tone of purple. 

C. scilloides is one of the less-desired species and it is the only one that is native to the eastern half of North America. Though certainly not as sought after as the Western species, its creamy white or lilac-tinged flowers on frothy racemes are quite pleasant. 

closeup of cream coloured Atlantic camas
A Raceme of Creamy White Camassia scilloides in Full Bloom

Among the notable cultivars are those with flowers of an especially rich or unusual colour, double or distinctly large flowers, and variegated foliage.

‘Alba’ is striking for the fullness of its flowers and their (very) creamy white colour. It is of mid height at about 80 centimetres. ‘Blue Danube’ bears flowers of an especially deep purple-blue colour. ‘Blue Heaven,’ on the other extreme, has flowers that are the palest tone of baby blue. If ‘Blue is for Boy’ then the demure baby pink blooms of ‘Pink Form’ are for girls. ‘Pink Star’ bears flowers with thick tepals of a very pale salmon pink tone.

‘Electra’ produces flowers that are a ‘normal’ shade of purple but these blooms are LARGE. ‘Plena’ bears creamy white or yellowish white double form flowers. 

Finally, ‘Sacajawea’ is named in honour of the native American squaw who interceded on behalf of Lewis and Clark and their men, and who assisted them in their expedition, including rooting out and cooking Camassia for the starving men. The flowers are off-white or a vanilla white, whereas the foliage is variegated, exhibiting white edging.

All of the above are cultivars of C. leichtlinii.

C. quamash ‘Blue Melody’ bears purplish flowers and has variegated foliage; leaves are edged with cream-yellow.

Habitat and Growing Conditions

Camassia species are native to a north-south swath of land in North America extending from the Rockies in the east to the Pacific in the west, and another north-south swath from Ontario down to Texas all the way east to the Atlantic coast. Camassia’s greatest concentration and diversity is in Oregon.

In their native habitat, Camassias sprout and spread in sunny prairies and flatlands, but also along streams and other wetlands, being partial to moist regions. They are also seen on mountainsides and hilly areas.

As an American-native flowering bulb, Camassia is something of a rarity as most flowering bulbs originate from Europe.

Camassia, well-bred and reserved, has not made any serious moves to colonise, or naturalise itself in, foreign lands. It has seen a deserved rise in popularity in the British Isles where it is slowly but steadily gaining traction with gardeners who are looking for something off the beaten track.  

This denizen of the American prairies is just hardy enough in most of the United Kingdom at a Hardiness of H4.

Camassia cusickii in focus with a garden in the background
The Narrow Tepals and Lilac-Purple Hue of Camassia cusickii

Where to Plant Camassia

First off, though Camassia can be planted in containers they do not do as well as they do in open ground for various reasons. Visually too, a Camassia will look awkward in a container; furthermore, it cannot offer anything at all in autumn and winter.

Camassias in bloom make a huge visual impact when they cover a sizeable area of land and, therefore, mass plantings are a great way to go. Try planting at least 15 bulbs in irregular drifts. Camassia flowers will look especially lovely on verges and slopes.

They can be mixed in with other bulbs such that their respective blooming seasons segue from one to the other so that you can enjoy flowers on the same patch of land from earliest spring to the end of summer.

Otherwise mix them up with spring wildflowers with which Camassias’ simple blooms will mingle well. These flowers can be utilised to create a wildflower meadow effect. 

This well-behaved bulb is not remotely invasive yet naturalises wonderfully well; as such, it will give pleasure for many years and also keep springing a surprise now and again.

Finally, this moisture-loving plant will do very well beside a stream or pond as long as the soil is not overly damp in autumn and winter.

flowering Camassia leichtlinii in a garden centre
Camassia leichtlinii Would be Brilliant on Verges and Slopes

Feeding, Care and Growing Tips

Like most bulbous plants, the straightforward way to grow Camassia is through bulbs. It is possible to grow them from seed but that method is not a very easy way to propagate what is an easy-care plant.

Also, seed-grown Camassias bloom after at least three years and even more.

You should choose bulbs that are large, evenly shaped, firm to the touch, and do not show any nicks or any loss of the bark-like covering or skin.

Though most any soil will do for this sporting bulb, a fertile loam amended with humus is ideal.

As a ‘moisture-loving’ bulbous plant Camassia does not object to damp or heavy soils in spring and summer. But when the bulb is dormant in autumn and winter, waterlogged soil can prove fatal. Therefore, soil should be well drained.

However, the plant prefers moist soil. As for soil pH, here too Camassia is unfussy but anything from Slightly Acidic to Slightly Alkaline will be just right.

A location where the plants get full sun, or full sun in the morning and filtered or dappled sun in the afternoon is best. Partial shade will do.

Bulbs are best planted in the September through November timeframe. Water the soil moderately before digging holes.

The planting depth should be two to three times the length of the bulbs. Bulbs should be spaced at least 10 centimetres, and up to 20 centimetres, apart. The pointed tip should be upwards.

After filling up the hole, do not pack the soil but give the ground a good watering so that the soil is firmed up.

You really don’t have to maintain these plants in any way; all you need do is to make sure that the soil does not dry out during the growing season – keep it consistently moist. Indeed, one might say that Camassias thrive on neglect and moisture!

Fertilising is strictly optional. Every couple of years the soil may be amended with some humus or a light sprinkling of bone meal may be worked into the soil though it must not be allowed to make contact with the bulb or stem.

If you anticipate a hard frost in winter, apply a good layer of mulch.

Camassia leichtlinii 'Alba'
Camassia leichtlinii ‘Alba’ Creamy-White, Thick Blooms

Pruning Camassia

Cut back stalks after the flowers are spent.

Allow the leaves to yellow and do not prune or cut back as the foliage synthesizes energy to replenish the bulb. It is this store of energy that sets up the bulb to push up stalks and to produce flowers the following year.

Leaves should be cut back only after they have turned brown and withered.

As a rule, Camassia bulbs should not be disturbed. However, if you have decided to separate and divide offsets, this can be done end of autumn to early winter when the bulb is dormant but before winter chill sets in.

Common Problems

One of the big positives of Camassias is that they are not known to suffer from any particular pests or diseases.

Where to Buy Camassia

Camassia quamash 'blue melody'
‘Blue Melody’ is a Lovely Cultivar of Camassia quamash

A large selection of these plants may well not be available at your neighbourhood nursery but a few of the popular varieties will likely be on display.

Both potted plants and bulbs are usually in stock at several, though not very many, online stores. Buying bulbs is the better option.

If you can find a merchant that sells a mix of 20 to 30 bulbs of several different varieties, then that would be a great buy.

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